davis



(NoModeL) A. G. DAVIS. Circuit Closer for Telephones.

No. 232,806. Patented Oct. 5,1880.

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AUGUSTUS G. DAVIS, OF BALTIMORE, MARYLAND.

CIRCUIT-CLOSER FOR TELEPHONES.

SPECIFICATION forming part of Letters Patent No.-232,806, dated October 5, 1880. Application filed May 31, 1880. (No model.)

To all whom it may concern.-

Be it known that I, AUGUSTUS G. DAVIS, of Baltimore city, State of Maryland, have invented certain new and useful Improvements in Circuit-Closers for Telephones; and I hereby .declare the same to be fully, clearly, and exactly described as follows, reference being had to the accompanying drawings, in which- Figure I is a rear elevation of that portion ofa telephone-box to which the circuit-closer and hook are attached, and Fig. 2 is a similar view of the tip of the circuit-closer.

The object of my invention is to obviate what has heretofore been a fruitful source of annoyance to users of telephones.

It frequently happens that when the hook which supports the telephone is returned to its normal position after using the instrument the circuit fails to become closed by reason of dust, insects, or particles of rubber from the driving-belt of the call-bell magneto-machine lodging between the surfaces designed to set up electric connection. To obviate this I provide an independent circuit-closer, which sets up connection when the telephone-hook is in its normal position indepenr'lently of the main circuit-closer, but which is thrown out of connection as the hook is pres: ed to one side.

In the accompanying drawings, A is the box, to which is pivoted, at E, the hook-block B, having the usual hook B. On the top of the block B is an insulator, I, of hard rubber, to which a circuit-closing plate, F, is secured. A pair of springs, G G, in connection with the wires, rest, or should rest, upon this plate F when the hook is in its normal vertical position; but, owing to the causes above referred to, they sometimes fail to do so.

To insure connection I attach to the casing orbox below the springs, at eitherside, a springlip, N N, connected by an insulated wire, L, as shown. These lips have serrated or roughened tips P, (see Fig. 2,) and when the hook B is vertical they press upon the under sides of the springs G G, setting up electric connection between them.

hen the hook is thrown to one side, as shown in Fig. 1, one of the springs G is lifted out of engagement with its lip N; but as the hook is returned to its normal position the separated tip P scrapes upon the under side of the spring, closing circuit.

It will be understood that this scraping motion back and forth, as the hook is moved from side to side, keeps the contact-surfaces clean, bright, and in condition to set up electric connection.

A wire, 0, is led from the block B to a clamping-screw, D, and the box is provided with the usual plate 0, having slots 0 G.

I have not considered it necessary to show nor describe the disposition of connectingwires, nor the other usual adjuncts of the box, as such form no part of my invention.

What I claim is- I. In a telephone circuit-closer, a serrated resilient tip adapted, as described, to close and break circuit, as and for the purpose set forth.

2. In combination with the pivoted hook and springs, the circuit-closers N N, as described.

3. In combination with the hook having plate F and springs G, the serrated lips N N, connected as described.

AUGUSTUS G. DAVIS.

\Vitnesses:

Jam. 1. llIADDOX, R. D. WILLIAMS. 

